261535564 has 12 divisors (see below), whose sum is σ = 458566024. Its totient is φ = 130516704.

The previous prime is 261535559. The next prime is 261535591. The reversal of 261535564 is 465535162.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 60417 + ... + 64600.

Almost surely, 2^261535564 is an apocalyptic number.

It is an amenable number.

261535564 is a deficient number, since it is larger than the sum of its proper divisors (197030460).

261535564 is a wasteful number, since it uses less digits than its factorization.

261535564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125544 (or 125542 counting only the distinct ones).

The product of its digits is 108000, while the sum is 37.

The square root of 261535564 is about 16172.0612168023. The cubic root of 261535564 is about 639.5044699427.

The spelling of 261535564 in words is "two hundred sixty-one million, five hundred thirty-five thousand, five hundred sixty-four".